Bottom Line:
Study-specific estimates were combined with inverse variance-weighted averages of logarithmic odds ratios (ORs) in fixed-effects models.From 8 studies involving 11542 persons, the pooled OR of AKI associated with an interval of 1 day or less between CAG and surgery was 1.21 (95% confidence interval (CI), 1.04 to 1.39) relative to an interval of more than 1 day.From 4 studies involving 5420 persons in the cardiopulmonary-bypass subgroup, the pooled OR of AKI associated with an interval of 3 days or less between CAG and surgery was 1.25 (95% CI, 1.07 to 1.43) relative to an interval of more than 3 days.

Background: Reports of the association between the time interval from coronary angiography (CAG) to cardiac surgery and risk of postoperative acute kidney injury (AKI) are controversial. We attempted to examine this association by conducting a meta-analysis.

Methods: We searched the Pubmed, MEDLINE, EMBASE, Web of Science databases, and the Cochrane Library from January 1966 to March 2013. A meta-analysis of studies reporting data for 1-day and 3-day time intervals between CAG and cardiac surgery was conducted after evaluation of heterogeneity and publication bias. Study-specific estimates were combined with inverse variance-weighted averages of logarithmic odds ratios (ORs) in fixed-effects models.

Results: From 8 studies involving 11542 persons, the pooled OR of AKI associated with an interval of 1 day or less between CAG and surgery was 1.21 (95% confidence interval (CI), 1.04 to 1.39) relative to an interval of more than 1 day. From 4 studies involving 5420 persons in the cardiopulmonary-bypass subgroup, the pooled OR of AKI associated with an interval of 3 days or less between CAG and surgery was 1.25 (95% CI, 1.07 to 1.43) relative to an interval of more than 3 days. The adjusted OR of the study in the cardiopulmonary bypass/ deep hypothermic circulatory arrest subgroup was 0.35 (95% CI, 0.17 to 0.73).

Conclusions: A time interval of 1 day or less between CAG and on-pump cardiac surgery was significantly associated with increased risk of AKI. A delay of on-pump cardiac surgery until 24 hours after CAG can potentially decrease postoperative AKI.

Figure 2: Forest plot for time interval, ≤1-day vs >1 day. The estimated odds ratio (OR) of each individual article corresponds to the middle of the squares, and the horizontal line gives the 95% confidence interval (CI). The sum of the statistics along with the summary OR is represented by the middle of the solid diamonds. The heterogeneity test statistic (I statistic) between articles is given below the summary statistics.

Mentions:
Four of the 8 individual studies demonstrated a statistically significant effect of a ≤ 1-day time interval on the incidence of AKI. Pooled analysis of the 8 studies revealed a significant increase in AKI risk by a factor of 1.21 with a ≤1-day time interval relative to >1 day in fixed-effects models (Figure 2). There was minimal trial heterogeneity (I2 = 24.0%, P = 0.238). Assessment of publication bias by visual examination of the funnel plot (Figure 3) and by application of Egger’s weighted regression test (P = 0.102) indicated no significant publication bias.

Figure 2: Forest plot for time interval, ≤1-day vs >1 day. The estimated odds ratio (OR) of each individual article corresponds to the middle of the squares, and the horizontal line gives the 95% confidence interval (CI). The sum of the statistics along with the summary OR is represented by the middle of the solid diamonds. The heterogeneity test statistic (I statistic) between articles is given below the summary statistics.

Mentions:
Four of the 8 individual studies demonstrated a statistically significant effect of a ≤ 1-day time interval on the incidence of AKI. Pooled analysis of the 8 studies revealed a significant increase in AKI risk by a factor of 1.21 with a ≤1-day time interval relative to >1 day in fixed-effects models (Figure 2). There was minimal trial heterogeneity (I2 = 24.0%, P = 0.238). Assessment of publication bias by visual examination of the funnel plot (Figure 3) and by application of Egger’s weighted regression test (P = 0.102) indicated no significant publication bias.

Bottom Line:
Study-specific estimates were combined with inverse variance-weighted averages of logarithmic odds ratios (ORs) in fixed-effects models.From 8 studies involving 11542 persons, the pooled OR of AKI associated with an interval of 1 day or less between CAG and surgery was 1.21 (95% confidence interval (CI), 1.04 to 1.39) relative to an interval of more than 1 day.From 4 studies involving 5420 persons in the cardiopulmonary-bypass subgroup, the pooled OR of AKI associated with an interval of 3 days or less between CAG and surgery was 1.25 (95% CI, 1.07 to 1.43) relative to an interval of more than 3 days.

Background: Reports of the association between the time interval from coronary angiography (CAG) to cardiac surgery and risk of postoperative acute kidney injury (AKI) are controversial. We attempted to examine this association by conducting a meta-analysis.

Methods: We searched the Pubmed, MEDLINE, EMBASE, Web of Science databases, and the Cochrane Library from January 1966 to March 2013. A meta-analysis of studies reporting data for 1-day and 3-day time intervals between CAG and cardiac surgery was conducted after evaluation of heterogeneity and publication bias. Study-specific estimates were combined with inverse variance-weighted averages of logarithmic odds ratios (ORs) in fixed-effects models.

Results: From 8 studies involving 11542 persons, the pooled OR of AKI associated with an interval of 1 day or less between CAG and surgery was 1.21 (95% confidence interval (CI), 1.04 to 1.39) relative to an interval of more than 1 day. From 4 studies involving 5420 persons in the cardiopulmonary-bypass subgroup, the pooled OR of AKI associated with an interval of 3 days or less between CAG and surgery was 1.25 (95% CI, 1.07 to 1.43) relative to an interval of more than 3 days. The adjusted OR of the study in the cardiopulmonary bypass/ deep hypothermic circulatory arrest subgroup was 0.35 (95% CI, 0.17 to 0.73).

Conclusions: A time interval of 1 day or less between CAG and on-pump cardiac surgery was significantly associated with increased risk of AKI. A delay of on-pump cardiac surgery until 24 hours after CAG can potentially decrease postoperative AKI.